Sheet-metal tank.



0. H. ZWBRMANN.

sum METAL TANK.

APPLICATION FILED SE Y Patented May 18, 1909.

lllln IIII buckle in enamelin the same" I i m 6 is an CARL H. ZWERMANN, or KALAMAZO'O, MICHIGAN.

SHEET-METAL TANK.

Specification of Letters Patent.

Patented May 18, 1909.

Application filed September 18, 1907. Serial No. 393,442.

To all whom it may concern: Be it known that I, CARL H. ZWERIM ANN, a citizen of the United States, residing at the city of Kalamazoo, county of Kalamazoo, and State of Michigan, have invented certain new and useful Improvements in Sheet- Metal Tanks, of which the following is a specification.

This inventionrelates to improvements in sheet metal tanks for use as closet tanksor for similar purposes.

The main objects of this invention are: first, to provide an improved construction of tank formed oi sheet metal, in which the joint of the parts of which it is made may be enameled satisfactorily without danger of breaking the enamel, either during the en'- amelin-g process or when the tank is in use; and second, to provide an improved construction of tank in which the expansion and contraction of the metal, due to the heat of the enameling process, will not rupture the joints or break the enamel.

Further objects, and objects relating to details of construction, wil definitely appear from the detailed description to follow.

I accomplish theo-bjects or" my invention by the devices and means described in the following specification.

The-invention is clearly defined and pointed out in the claims.

A structure embodying the features of invention, is clearly illustrated in the accompanyingdrawing'forming a part ofthis specific ation', in which:

Figure I is a front elevation ofa tank embodying the features of my invention, a poi" tion being broken away to show the structural details; Fig. 2 is a plan view oimjy improved tank, with a portion of the cover broken away; Fig. 3 is an inverted orbottom view of my improved tank; Fig. is a rear view thereof Fig. 5'is an enlarged detail taken on a line corresponding to line 55'of Fig. 4, showing the means for making the rear or back wall rigid so that it is not likely to enlarged detail, taken on lines 66' of Fig. 4-, showing the joint for the rear tothetop, bottom and side walls and Fig- 7 is a detail view showing the metal somewhat ex'aggen ate'd prior to the weldingoi' the rear wall to the top, bottom and side walls.

In the drawing, similar numerals oi" reference'refer tosi-mil'ar parts throughout the'sev' eral views.

In the welding of sheet metal, serious dil ficulties are eiicou'ntered. In the matter of welding by electricity,- or the electric arc, a perfect weld is accomplished only in a very small area, andthe parts have only been successfully welded by a butt or upset weld. It is, however, possible to weld by a blow-pipe process, by bringing the edges of the metal together in various ways; but, under-such circumstances, there are likely to be crevices between the parts where they are brought together at an acute angle. These crevices cannot be cleaned by the pickle used in rem'ovii rg scale and rust preparatory to enameling', and unless the metal is perfectly clean of scale or rust, or if there isany surface that is not bright and clean, the enamel will not properly adhere to it. It soon peels oil and opens up, and, as the enamel itself is very fragile, there is soon a crack or break through the same to the metal,-which quickly rusts and the whole enameled article is destroyed. This matter of rusting is'o'l course more likely to occur insuch an article as a closet tank, the same is constantly exposed to the action of waterl It is the main object of this invention to produce a tank made up of sheet metal in which the parts can be welded together and to avoid any narrow crevices or cracks that cannot be properly cleaned to receive the enamel; and also to produce a structure which will not warp" and become injured by the heat incident to the enameling process.

In the'stru'cture illustrated, the front wall 1, the side wa-lls'2', the bottom 3 and the top 4, areformed ot a single piece of metal, the same being died orpun'ch'ed up, with rounded corners, so that the metal is not materially weakened in this process. As tanks of this construction are comparatively narrow from front to rear, thi's'punchi'ng out from a single piece can be read i y accomplished. The top wall 4 is punched out toforin a suitable opening and the" cover flange 5' is formed therein. A suitable cover, as 11, also formed from sheet metal, is provided. The rear wall 6 is preferably provided with diagonal corrugz tions or ribs 7 which serve to strengthen the same so that buckling is prevented during the enaineling process The back- 6 18 provi'd ed with a rearwardl y' projecting flange 8 at-its edges, the flange being adapted tofit within the top, bottom and side walls. This flange 8 is' curved and is provided with an upset portion 9, theface of which is substantially parallel with and fits against the top, bottom and side walls, as clearly appears in Fig. 7, the upset portion from the flange being illustrated at 10. This forms a comparatively broad notch between the rear wall and its meeting walls, as clearly appears from the drawing. The rear wall is welded to its meeting walls by a hydrogen blow-pipe which is applied to the edge of the metal, and welds the same into the form appearing in Fig. 6. After the rear wall is welded to the top, bottom and side walls, as described, the tank is treated to the usual pickle for removing the scale and rust, and is then suitably cleaned and a coating of enamel, as 12, is applied on the inside; and, owing to the fact that there are no narrow crevices in the meeting edges of the walls, the enamel flows into the joint and perfectly contacts with and adheres thereto, the joint being sufliciently wide to allow a considerable quantity to flow into the same. The advantage of this form of joint is that, owing to the curve of the joint flange, any expansion or contraction in the heating process is taken up thereby, so that the joint is not affected. The joints for the bottom front wall to the side, top, and bottom, being curved, they are in the most desirable form to receive the enamel.

I preferably provide the structure with an outer coating 13. Apertures 14 and 15 are provided in the bottom wall to receive the supply and discharge pipes, and in the rear walls are openings 16 for the purpose of securing the tank to the wall or support; and in the front wall is an opening 17 to receive the operating mechanism. These apertures are formed prior to the enameling process, so that there are no exposed edges of the bare metal.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

- 1. A sheet metal tank comprising front, side, top and bottom walls, formed from a single piece of sheet metal, the top wall having a cover-opening therethrough, the said opening being provided with an upwardly projecting flange at its edges, adapted to receive the cover; a rear wall having diagonal corrugations therein, said rear wall being provided with an outwardly-projecting curved flange at its edges, the edge of said flange being offset and substantially parallel to the edge portion of the bottom, top and side walls into which it is fitted and to which it is joined by welding, there being a notch at the joint; and an interior coating of enamel extending into said notch, as specified.

2. A sheet metal tank comprising front, side, top and bottom walls formed from a single piece of sheet metal; a rear wall having diagonal corrugations therein, said rear wall being provided with an outwardly-projecting curved flange at its edges, the edge of said flange being offset and substantially parallel to the edge portion of the bottom, top, and side walls into which it is fitted and to which it is joined by welding, there being a notch at the joint; and an interior coating of enamel, extending into said notch, as specified.

3. A sheet metal tank comprising front, side, top and bottom walls formed from a single piece of sheet metal, the top wall having a cover-opening therethrough, the said opening being provided with an upwardly pro- 'ectin flan e at its ed es ada ted to receive 1 a b a 7 i the cover; a rear wall provided with an outwardly-projecting curved flange at its edges, the edge of said flange being offset and substantiai y parallel to the edge portion of the bottom, top and side walls into which it is fitted and to which it is joined by welding, there being a notch at the joint; and an interior coating of enamel extending into said notch, as specified.

1. A sheet metal tank comprisingfront, side, top and bottom walls formed from a single piece of sheet metal; a rear wall provided with an outwardly-projecting curved flange at its edges, the edge of said flange being oifset and substantially parallel to the edge portion of the bottom, top, and side walls into which it is fitted and to which it is joined by welding, there being a notch at the joint; and an interior coating of enamel extending into said notch, as specified.

5. A sheet metal tank comprising front, side, top and bottom walls; a rear wall provided with an outwardly-projecting curved flange at its edges, the edge of said flange being offset and substantially parallel to the edge portion of the bottom, top and side walls into which it is fitted and to which it is joined by welding, there being a notch at the joint; and an interior coating of enamel, extending into said notch, as specified.

6. A sheet metal tank comprising front, side, top and bottom walls, formed from a single piece of sheet metal; a rear-wall provided with an outwardly-projecting curved flange at its edges, said flange being fitted into and joined at its edges to the edges of said top, bottom and side walls, by welding, there being a notch at the joint; and an interior coating of enamel extending into said notch.

7. A sheet metal tank comprising front, side, top and bottom walls; a rear wall provided with an outwardly-projecting curved flange at its edges, said flange being fitted into and joined at its edges to the edges of the said top, bottom, and side walls, by weld.

ing, there being a notch at the joint; and an interior coating of enamel extending into said notch.

8. A sheet metal tank comprising front, side, top and bottom walls, formed from a single piece of sheet metal; a rear wall pro xii vided with an outwardly-projecting curved flange at its edges, said flange being fitted into and oined at its edges to the edges of the said top, bottom and side walls, bf. welding, there being a notch in the flange at the joint adapted to receive a coating or" enamel.

9. A sheet metal tank comprising front, side, top and bottom walls and a rear wall provided with an outwardlyprojecting curved flange at its edges, said flange being fitted into and joined at its edges to the edges of the said top, bottom and side walls, by welding, there being a notch in the flange at the joint adapted to receive a coating of enamel.

10. A tank comprising sheet metal walls, one or" which is provided with an outwardlyprojecting curved flange at its edges, the outer edge of said flange being ofiset and substantially parallel to the meeting wall to which it is fitted and joined to said wall by welding, there being a comparatively broad notch at the joint; and an interior coating of enamel extending into said notch.

which it is fitted and joined to said wall bv welding, there being a comparatively broad notch at the joint adapted to receive a coating of enamel.

12. A tank comprising sheet metal walls,

one of which is provided with an outwardlyprojecting curved flange at its edge, said flange being oined at its edge to the edge oi the meeting wall by welding, there being a comparativelj broad notch at the j oint; and

an interior coating of enamel extending into said notch.

In witness whereof, I have hereunto set my hand and seal in the pres nce of two witnesses.

CARL H. ZlVER-MANN.

Witnesses ADELAIDE I. ADAMS, GERTRUDE TALLMAN. 

